Sewing-machine.



H. BRIGGS.

SEWING MACHINE.

APPLICATION FILED 30V. 24, 1906.

Patented May 26, 1914.

2 SHEETS-SHEET 1.

a w s W H. BRIGGS.

SEWING MACHINE.

APPLICATION FILED NOV. 24, 1906.

Patented May 26, 1914.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

HENRY BRIGGS, OF HASBROUGK HEIGHTS, NEW JERSEY.

SEWING-MACHINE.

To all whom it may concern:

Be it known that I, HENRY Bmccs, a eiti-' zen of the UnitedStates,'residing at. Hasbrouck Heights, in the county of Bergen andState of New Jersey,-have invented certain new and useful Improvementsin Sewing-Machines; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

The present invention relates to slide locking devices for sewingmachines and more particularly to devices for locking the back gage andback rest slides of inseam shoe-sewing machines.

In inseam shoe-sewing machines it is common to providedevices forguiding and supporting the lasted shoe during the operation of thesewing instrumentalities, such devloes being known as back gages or backrests according to their location and point of engagement with the shoe.Such devices are usually made to be movable either by the pressure ofthe work thereagainst or through the mechanism of the sewing machine, atcertain times in the operation of the machine, so as to permit theposition of the work to be changed as it is fed, while during theformation and setting of the stitch these devices are locked inposition, to prevent shifting, at such time, of the work. To look theback rest and back gage slides in position pawl and ratchet mechanismshave heretofore usually been employed; These mechanisms have not howeverbeen entirely satisfactory since they do not always look the slides inexactly the desired position on account of lost motion between the teethof the ratchets and the L locking pawls. Furthermore these mechanismsare not durable and give trouble on.

account of the breaking of the pawls or the .teeth of the ratchets.

The object of the present Invention is to provide a simple and improvedmeans for looking the back rest and back gage slides of With this objectin view the presentinventionconsists in the devicesand combma-Specification of Letters Patent. Patented May 26, 1914, Applicationfiled November24, 1906. Serial No. 344,828.

tions of devices hereinafter described, as defined 1n the claims,

In the drawings F lgure 1 is a side elevathe preferred form of thepresent invention, Fig. 2. is a detail view, in side elevation, of theback gage and back rest slides together with their locking mechanism,and Fig. 3 is a rear end elevation of the parts illustrated in Fig. 2.

Theinvention is illustrated as embodied in a chain-stitch inseam-sewingmachine of the type shown and described in Letters Patent of the UnitedStates No. 687,719, granted December 3,1901, to thisapplicant. The backgage of the machine is indicated at 1 and the back rest at 2. The backgage longitudinally in ways formed in the frame of the machine, and acam lever 4 is provided for moving the back gage backwardly as is usualin this class of machines. The back gage is returned to a forwardposition by the usual spring 5.

The locking mechanism for the back gage slide comprises a fixed lockingmember 6 provided with a friction surface parallel with the length ofthe slide 3, and a movable locking member 7 pivoted at one end, by meansof a screw 8, to the slide 3 and provided with a friction surface 9parallel with the length of the slide. Below the slide is chine, anoscillating roll-supporting member 11' provided with a hardened face 12which is slightly inclined to the lower friction surface of the lockingmember 7. Between the roll-supporting member 11 and the locking member 7is interposed a clutch roll 13 which may be in the form of a hardenedsteel ball or cylinder.- 1

The backrest 2 is mounted upon a slide 14 provided with a pivotedlocking member 15,- and the latter is engaged by a fixed controlled by aroll supporting member 18, all substantially like the correspondingdevices connected with the back gage, except that the parts areinverted. The slide 14 is drawn forward by a spring ,lfLfixed. at itsrear end to an arm 20 projecting from the slide and at its forward endto the frame of the machine. The roll-supporting member 11 is providedwith an arm 21 arranged to tion of a shoe-sewing machine embodyinglocking member 16 and a clutch roll 17,'

1 is mounted upon a slide 3 which moves 1 pivoted at 10, upon the frameof the mabe engaged by an adjusting screw 22 on an,

arm 23 on the roll-supporting member 18-, and the latter is providedwith a second arm 24 arranged to be engaged by a lever 25 pivoted at 26on the'frame of the machine. The lever 25 extends into the path ofmovement of a cam lever 27 actuated by a cam 28 on the cam shaft 29 ofthe sewing machine. The cam path is not shown in the drawing since itsform will be obvious to those skilled in the art and can be readilyproduced by any designer of shoe sewing machines.

The train of mechanism just described operates to oscillate the rollsupporting members 11 and 18 at suitable times to unlock the slides 3and 14, the member 18 being oscillated directly by the lever 25 when thelower end of the lever 27 moves to the right and the member 11 beingoscillated by the enagement of the screw'22 with the arm 21. %y means ofthe adjusting screw 22 the movements of the members 18 and 11 can betively with projections 30 and 31 at the rear of the rolls. The rollsupporting members are returned-to locking position by means of a coiledspring 32 connecting the members, and to insure the return movement ofthe rolls the roll supporting members are provided with projections 33and 34 at the front of. the rolls. When the roll supporting mem-' bersare in locking position as indicated in Fig. 2 any backward pressureexerted upon the slide 14 is resisted by the roll 17 pinching betweenthe locking member 15 and the" supporting surface of the member 18 andthereby, by the wedging action of the roll and the toggle action of themember 18, pressing the member 15 firmly against the fixed lockingmember 16. A backward pressure exerted upon the slide 3 is resisted in asimilar manner by the action of the roll 13, its supporting member 11and the movable and fixed locking members 7 and 6. The slides are not,however, locked against forward movement but are free tomove forwardunder the force of the springs connected therewith as soon as the slidesare relieved of backward pressure. The locking devices lock the slidesaccurately in the positions to which they are movedwhile un- \lockedwithout any lost motion and without any tendency to force the slidestforward. The greater the backward pressure exerted upon the slides themore firmly will the movable locking members be forced against the ingand unlocking the slides. The plate 35 (see Fig. 3) covers the lockingdevices to prevent the esca e of the rolls. This plate- 18 not shown inig. 2.

The construction illustrated in the drawings and above specificallydescribed embodies the features of the present-invention in the bestform that has yet been devised. It is to be understood, however, thatthe invention is not limited, to the details of construction of theillustrated embodiment but may be embodied in other forms within thescope of the claims.

The invention having been described what is claimed is 1. An inseam shoesewing machine having, in combination, a work-rest slide, a fixedfriction-lockin member, a movable locking member pivota ly connected tothe slide, and

mechanism for intermittently pressing the locking members together tolock the slide, substantially as described.

2. An inseam shoe sewing machine having, in combination, a work restslide movable toward and from the shoe provided with a longitudinalfriction-surface, a locking mechanism to lock the slide against backwardmovement comprising a pivotally-mounted roll-supporting member providedwith a roll-supporting surface adjacent to said friction surface, aclutch roll located between and in engagement with said surfaces andmechanism for intermittently swinging the roll-supporting member aboutits pivotal support to release the roll and the slide, substantially asdescribed.

3. An inseam shoe sewing machine having, in combination, a back-gageslide and a back rest slide provided with longitudinal frictionsurfaces,pivotally-mounted members rovided with roll supporting surfaces, clutcrolls interposed between said members and said surfaces, a springconnecting said members and tending to throw them into 0 erativeposition, arms connected to said members and engaging each other forcausing the simultaneous actuation of said members, and mechanismconnected with one member and operating intermittently to throw themembers into inoperative position, substantially as described. 7

4. An inseam shoe sewing machine, having, in combination, a work restslide, a fixed friction locking member, a cooperating friction lockingmember movably mounted on the slide, a clutch roll arranged to force thelocking member against the fixed member, a support for said roll, andmeans for actuating said support to lock and unlock the slide,substantially as described.

, 5. An inseam shoe sewing machine, hav- 7 ing, in combination, a workrest slide movable toward and from the shoe provided with a longitudinalfriction surface, a clutch roll engaging said surface to lock the slideagainst backward movement, a member engaging the roll provided with aroll supporting surface inclined to said friction surface and with arojection at the rear of the roll, and means or actuating said member tore- 1 15 lease the slide, substantially as described.

' In testimon vwhereof I aflix my signature, in presence 0 twowitnesses.

1 v HENRY BRIGGS. Witnesses:

FRED O. FISH, ALFRED H.

